The present invention relates to an optical jack for receiving an optical plug holding an optical fiber and, more particularly, to an ultraminiature optical jack that is incorporated in small, portable electronic equipment such as digital audio equipment, portable telephone or portable data terminal.
There is widely used an optical jack (a connector for photoelectric conversion) that contains a luminous element or light receiving element in its body and transmits and receives light between it and an optical fiber of the optical plug inserted in a sleeve provided at one end of the jack body. With downsizing of small, portable electronic equipment, further miniaturization of such an optical jack is particularly demanded.
At present, there is widespread an optical plug having a diameter of 3.5 mm and a length of 15 mm, and to comply with such specifications, a so-called 3.5 optical jack is now used. Since, however, there are already proposed small-diameter optical plugs, for example, 2.5 and 2 mm in diameter, it is necessary to offer ultraminiature optical jacks that meet such specifications.
Usually, the optical jack of this kind is mounted on a circuit board by soldering. As the optical jack is miniaturized, its soldering strength (mounting strength) lowers and cannot sufficiently withstand forces applied when the mating optical plug is inserted into and removed from the jack or when it is pinched.
It is therefore an object of the present invention to provide an ultraminiature optical jack that achieves sufficient mounting strength.
Another object of the present invention is to provide an ultraminiature optical jack that achieves required mounting strength but can be reduced in depth.
According to the present invention, there is provided an ultraminiature optical jack that is mounted on a circuit board, for receiving an optical plug having a length-to-diameter ratio of less than 4, said optical jack comprising:
a substantially box-shaped resin-made body having formed integrally therewith on the front end side thereof a sleeve for receiving an optical plug and having in its rear end portion a luminous element housing section open in its rear end and bottom;
two contact piece members formed of resilient metal and received in said luminous element housing section, said contact piece members having panel portions, resilient contact pieces extended from marginal edges of said panel portions for firmly holding therebetween the peripheral surface of said optical plug inserted in said sleeve, and terminal portions extended integrally from the lower marginal edges of said panel portions and projecting squarely outwardly from the intermediate portions of the both sides of said body in its front-to-back direction, said terminal portions being soldered to said circuit board;
a luminous element hosed in said hosing section and having a plurality of element terminals; and
a metal cover fitted on said body to cover the top, both side surfaces and rear end face portion thereof and having a pair of soldering portions extended outwardly of both sides of said body from said metal cover, said pair of soldering portions being soldered to said circuit board.
In the ultraminiature optical jack, a notch may be formed in the portion of said metal cover covering the top of said body so that said element terminals project out rearwardly of said body through said notch.
In the ultraminiature optical jack, said element terminals may be extended downwardly from the underside of said body and said metal cover may have a rear solder joint portion extending rearwardly of said body.
In the ultraminiature optical jack, a pair of engage holes may be formed through said metal cover for engagement with engage projections formed on both side surfaces of said body.
In the ultraminiature optical jack, said body may be formed open in is rear end and the portion of said metal cover covering said open end portion may be provided with a pair of upturned projections 24a projecting toward said body 11 in a manner to prevent said luminous element from falling off said body to hold said luminous element in said housing section.
In the ultraminiature optical jack may be further provided with a metal band fitted on the front end portion of said body to cover the top and both side surfaces thereof, said metal band having at its both ends soldering portions extended outwardly of the both sides of said body.
In the ultraminiature optical jack, notches may be formed in the outside marginal edge of each of said terminal portions or a through hole may be formed through each terminal portion to provide increased interface distance.